The Amazing Brain: Is Neuroscience the Key to What Makes Us Human?
A BRIEF TOUR OF HUMAN CONSCIOUSNESS
By V.S. Ramachandran
Pi Press, $23.95, 192 pages, illus.
While in medical school, V.S. Ramachandran, director of the Center for Brain and Cognition at the University of California at San Diego, encountered a patient given to episodes of alternately weeping and laughing uncontrollably. This display of emotional mercuriality struck Ramachandran as a replay of the human condition. "Were these just mirthless joy and crocodile tears, I wondered? Or was he actually feeling alternately happy and sad, the same way a manic-depressive might, but on a compressed scale?"
During his professional career as a neurologist and researcher, Ramachandran has retained his curiosity and formulated about his patients the "kinds of very simple questions that a schoolboy might ask but are embarrassingly hard for experts to answer."
For example, "Why does this patient display these curious symptoms? What do the symptoms tell us about the working of the normal brain?" In the process, Ramachandran has learned that many patients with damage in a localized part of the brain often suffer a highly selective loss of one specific function with other functions remaining unaffected--an indication that the damaged area is normally involved somehow in mediating the impaired function. Further, some of these selective impairments can be both fascinating and informative.
Consider David, a patient of Ramachandran's who emerged from a coma mentally intact, with the exception of the bizarre delusion that his mother had been replaced by an impostor.
Further evaluation revealed an important distinction: Although David couldn't recognize his mother when encountering her face to face, he had no trouble identifying her when talking to her on the telephone. What could account for such an anomaly?
It turns out that separate pathways lead from the auditory and visual regions of the brain to the amygdala, an important component of the brain's emotional circuitry. In David's case, the fibers connecting the visual center to the amygdala were no longer functioning normally. As a result, whenever he looked at his mother he no longer got that warm feeling of recognition that normally accompanies seeing one's parent. He therefore accused her of being an impostor.
The auditory fibers in David's brain, in contrast, retained their normal connections with the amygdala. Consequently, the emotional linkage of voice and person remained intact and David recognized his mother's voice.
"This is a lovely example ... of neuroscience in action; of how you can take a bizarre, seemingly incomprehensible neurological syndrome ... and then come up with a simple explanation in terms of the known neural pathways in the brain," writes Ramachandran.
Other bizarre but informative disorders taken up in this wide-ranging book include phantom limb (the sensation that an amputated arm or leg is still present); synesthesia (a condition in which the senses are mingled so that the affected person tastes a shape, or sees a color in a sound or a number); and achromotopsia (seeing the world in shades of gray, like a black-and-white film).
"By studying neurological syndromes which have been largely ignored as curiosities or mere anomalies, we can sometimes acquire novel insights into the functions of the normal brain," the author writes. Moreover, he suggests, "the study of patients with neurological disorders has implications for the humanities, for philosophy, maybe even for aesthetics and art."
While all this sounds reasonable, Ramachandran sometimes comes across like the proverbial carpenter who approaches all issues as resolvable via the use of hammer and nail. Specifically, he claims that neuroscience can answer (or soon will) "some lofty questions that have preoccupied philosophers since the dawn of history: What is free will? What is body image? What is art? What is the self? Who am I?"
At times, his reductionism pushes the envelope a bit: "We recognize that life is a word loosely applied to a collection of processes--DNA replication and transcription, Krebs cycle, Lactic acid cycle, etc., etc." At another point, after naming several brain structures he asserts, "Know how they perform their individual operations, how they interact, and you will know what it means to be a conscious human being."
Despite such extravagant and hubristic statements, no one so far has been able to perform the alchemical conversion whereby "To be or not to be" can be understood in terms of neurotransmitters and brain structures. Nor is such a conversion ever likely since, as philosopher Gilbert Ryle pointed out, it would invoke the category mistake: intermingling separate and distinct orders of discourse.
For example (Ryle's own example, incidentally), the university that I attended cannot be equated except associatively with the buildings comprising it. True, the buildings when considered together may loosely be referred to as "the university"; but the entity defined by that word is far more nuanced than just real estate.
Likewise, can the mind be explained totally in terms of the brain? Ramachandran thinks so and while, on the whole, I tend to agree with him, I also have to admit to a trace of agnosticism on the question.
Not surprisingly, when discussing mental illness, Ramachandran is strictly in the neuropsychiatric camp: Neurology and psychiatry are so interpenetrated that future treatments and cures can only come about via increased knowledge about the brain. As a neurologist and neuropsychiatrist myself, I certainly don't disagree with that claim. Many psychiatrists, however, may find Ramachandran's phrasing of the matter a bit off-putting ("it is only a matter of time before psychiatry becomes just another branch of neurology").
But his heart is in the right place. Freudianism and other guru-driven "isms" are dead, replaced by an emphasis on the brain. Indeed, so much has been learned about mental illness in the past two decades as a result of brain research that it's difficult to imagine any alternative approach.
My principal criticism of this book concerns its odd arrangement: 112 pages of text accompanied by 44 pages of endnotes. As he mentions in his introduction, Ramachandran holds a rather quirky notion about endnotes ("the real book is in the endnotes"). Perhaps that's true, but the delegation of large parts of the narrative to the endnotes presents several difficulties.
For one, this text-endnote dichotomy makes it too easy for both author and editor to forsake their most important duty: organizing the material into a free-flowing narrative. Second, on occasion--such as his description of the more exotic forms of synesthesia--the endnotes prove even more interesting than the main text.
Finally, material in the text is sometimes repeated in the endnotes, such as Ramachandran's explanation of the origin of the ear. And given this emphasis on the endnotes, why are the notes corresponding to the last two citations in the final chapter missing?
Admittedly, these are minor quibbles that detract not at all from a perfectly marvelous book. Overall, reading Ramachandran in A Brief Tour of Human Consciousness is like listening to a John Coltrane solo: The man is here, there, and everywhere; he's inventive, inspired, wildly speculative, and yet disciplined by the demands of his craft. Give him a fact about the brain and he'll link it with a quote from Shakespeare; a nanosecond later he'll suggest an experiment that you can carry out in your living room to learn more about the fact.
To Ramachandran, the brain is more than an enchanted loom, and wider than the sky; it's an endless source for manic excitement, intriguing questions, profound reflections and a zany humor ("our brains ... if raised in a culture-free environment like Texas would barely be human"). And like Coltrane, Ramachandran leaves you marveling at how he does it; wondering how he's learned all that he knows; and spinning like a top from the effort of trying to absorb all the wonderful things that he's telling you.
A Brief Tour of Human Consciousness is well worth the effort. You'll be entertained, provoked, amused and--most important of all--eager to learn more.
(c) 2004 News World Communications Inc.
|Printer friendly Cite/link Email Feedback|
|Title Annotation:||A Brief Tour of Human Consciousness|
|Publication:||World and I|
|Article Type:||Book Review|
|Date:||Nov 1, 2004|
|Previous Article:||A Tale of Heroism in Czechoslovakia's "Velvet Revolution".|
|Next Article:||Democracy Yes, but How?|